Fig. 1.

Cell responses to vapours from bananas. a Evaluation of banana flavour. Forty evaluators choose the stronger banana-like scent one from two bananas (paired test). For analyses, the score for selected banana was set to 1 and another 0. When the evaluator selected neither, both were 0. There is a significant statistical difference by Welch’s t test (*p < 0.05). b Scheme of cell stimulation; two puffer pipettes contained stimulants originated from type a or type b bananas. Sliced bananas were placed in containers for 3 h and volatile molecules in containers were adsorbed into filter papers that were wetted with normal Ringer’s solution and were adhered to the back of the lid. Solutions were then squeezed and applied to single olfactory receptor cells (ORCs) under the voltage clamp. c Current responses to stimulants from strong smelling bananas (type a). d Current responses to stimulants from weak smelling bananas (type b). b, c were obtained from the same ORC. The same banana samples (type a and b) were used for human psychology tests and cell experiments throughout a–d